[ALSA] Unregister device files at disconnection

Orignally proposed by Sam Revitch <sam.revitch@gmail.com>.
Unregister device files at disconnection to avoid the futher accesses.
Also, the dev_unregister callback is removed and replaced with the
combination of disconnect + free.
A new function snd_card_free_when_closed() is introduced, which is
used in USB disconnect callback.

Signed-off-by: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Jaroslav Kysela <perex@suse.cz>

13 files changed, 146 insertions, 170 deletions

diff --git a/sound/core/control.c b/sound/core/control.c
index e9c8854d2f7b..f0c7272a2d48 100644
--- a/sound/core/control.c
+++ b/sound/core/control.c
@@ -1375,6 +1375,11 @@ static int snd_ctl_dev_disconnect(struct snd_device *device)
         struct snd_card *card = device->device_data;
         struct list_head *flist;
         struct snd_ctl_file *ctl;
+        int err, cardnum;
+
+        snd_assert(card != NULL, return -ENXIO);
+        cardnum = card->number;
+        snd_assert(cardnum >= 0 && cardnum < SNDRV_CARDS, return -ENXIO);
 
         down_read(&card->controls_rwsem);
         list_for_each(flist, &card->ctl_files) {
@@ -1383,6 +1388,10 @@ static int snd_ctl_dev_disconnect(struct snd_device *device)
                 kill_fasync(&ctl->fasync, SIGIO, POLL_ERR);
         }
         up_read(&card->controls_rwsem);
+
+        if ((err = snd_unregister_device(SNDRV_DEVICE_TYPE_CONTROL,
+                                         card, -1)) < 0)
+                return err;
         return 0;
 }
 
@@ -1404,23 +1413,6 @@ static int snd_ctl_dev_free(struct snd_device *device)
 }
 
 /*
- * de-registration of the control device
- */
-static int snd_ctl_dev_unregister(struct snd_device *device)
-{
-        struct snd_card *card = device->device_data;
-        int err, cardnum;
-
-        snd_assert(card != NULL, return -ENXIO);
-        cardnum = card->number;
-        snd_assert(cardnum >= 0 && cardnum < SNDRV_CARDS, return -ENXIO);
-        if ((err = snd_unregister_device(SNDRV_DEVICE_TYPE_CONTROL,
-                                         card, -1)) < 0)
-                return err;
-        return snd_ctl_dev_free(device);
-}
-
-/*
  * create control core:
  * called from init.c
  */
@@ -1430,7 +1422,6 @@ int snd_ctl_create(struct snd_card *card)
                 .dev_free = snd_ctl_dev_free,
                 .dev_register = snd_ctl_dev_register,
                 .dev_disconnect = snd_ctl_dev_disconnect,
-                .dev_unregister = snd_ctl_dev_unregister
         };
 
         snd_assert(card != NULL, return -ENXIO);
diff --git a/sound/core/device.c b/sound/core/device.c
index 6ce4da4a1081..ccb25816ac9e 100644
--- a/sound/core/device.c
+++ b/sound/core/device.c
@@ -71,7 +71,7 @@ EXPORT_SYMBOL(snd_device_new);
  * @device_data: the data pointer to release
  *
  * Removes the device from the list on the card and invokes the
- * callback, dev_unregister or dev_free, corresponding to the state.
+ * callbacks, dev_disconnect and dev_free, corresponding to the state.
  * Then release the device.
  *
  * Returns zero if successful, or a negative error code on failure or if the
@@ -90,16 +90,14 @@ int snd_device_free(struct snd_card *card, void *device_data)
                         continue;
                 /* unlink */
                 list_del(&dev->list);
-                if ((dev->state == SNDRV_DEV_REGISTERED ||
-                     dev->state == SNDRV_DEV_DISCONNECTED) &&
-                    dev->ops->dev_unregister) {
-                        if (dev->ops->dev_unregister(dev))
-                                snd_printk(KERN_ERR "device unregister failure\n");
-                } else {
-                        if (dev->ops->dev_free) {
-                                if (dev->ops->dev_free(dev))
-                                        snd_printk(KERN_ERR "device free failure\n");
-                        }
+                if (dev->state == SNDRV_DEV_REGISTERED &&
+                    dev->ops->dev_disconnect)
+                        if (dev->ops->dev_disconnect(dev))
+                                snd_printk(KERN_ERR
+                                           "device disconnect failure\n");
+                if (dev->ops->dev_free) {
+                        if (dev->ops->dev_free(dev))
+                                snd_printk(KERN_ERR "device free failure\n");
                 }
                 kfree(dev);
                 return 0;
diff --git a/sound/core/hwdep.c b/sound/core/hwdep.c
index cbd8a63282b6..9aa9d94891f0 100644
--- a/sound/core/hwdep.c
+++ b/sound/core/hwdep.c
@@ -42,7 +42,7 @@ static DEFINE_MUTEX(register_mutex);
 static int snd_hwdep_free(struct snd_hwdep *hwdep);
 static int snd_hwdep_dev_free(struct snd_device *device);
 static int snd_hwdep_dev_register(struct snd_device *device);
-static int snd_hwdep_dev_unregister(struct snd_device *device);
+static int snd_hwdep_dev_disconnect(struct snd_device *device);
 
 
 static struct snd_hwdep *snd_hwdep_search(struct snd_card *card, int device)
@@ -353,7 +353,7 @@ int snd_hwdep_new(struct snd_card *card, char *id, int device,
         static struct snd_device_ops ops = {
                 .dev_free = snd_hwdep_dev_free,
                 .dev_register = snd_hwdep_dev_register,
-                .dev_unregister = snd_hwdep_dev_unregister
+                .dev_disconnect = snd_hwdep_dev_disconnect,
         };
 
         snd_assert(rhwdep != NULL, return -EINVAL);
@@ -439,7 +439,7 @@ static int snd_hwdep_dev_register(struct snd_device *device)
         return 0;
 }
 
-static int snd_hwdep_dev_unregister(struct snd_device *device)
+static int snd_hwdep_dev_disconnect(struct snd_device *device)
 {
         struct snd_hwdep *hwdep = device->device_data;
 
@@ -454,9 +454,9 @@ static int snd_hwdep_dev_unregister(struct snd_device *device)
                 snd_unregister_oss_device(hwdep->oss_type, hwdep->card, hwdep->device);
 #endif
         snd_unregister_device(SNDRV_DEVICE_TYPE_HWDEP, hwdep->card, hwdep->device);
-        list_del(&hwdep->list);
+        list_del_init(&hwdep->list);
         mutex_unlock(&register_mutex);
-        return snd_hwdep_free(hwdep);
+        return 0;
 }
 
 #ifdef CONFIG_PROC_FS
diff --git a/sound/core/init.c b/sound/core/init.c
index 1ecb029ff4c9..5850d99d21e3 100644
--- a/sound/core/init.c
+++ b/sound/core/init.c
@@ -327,22 +327,10 @@ EXPORT_SYMBOL(snd_card_disconnect);
  *  Returns zero. Frees all associated devices and frees the control
  *  interface associated to given soundcard.
  */
-int snd_card_free(struct snd_card *card)
+static int snd_card_do_free(struct snd_card *card)
 {
         struct snd_shutdown_f_ops *s_f_ops;
 
-        if (card == NULL)
-                return -EINVAL;
-        mutex_lock(&snd_card_mutex);
-        snd_cards[card->number] = NULL;
-        mutex_unlock(&snd_card_mutex);
-
-#ifdef CONFIG_PM
-        wake_up(&card->power_sleep);
-#endif
-        /* wait, until all devices are ready for the free operation */
-        wait_event(card->shutdown_sleep, card->files == NULL);
-
 #if defined(CONFIG_SND_MIXER_OSS) || defined(CONFIG_SND_MIXER_OSS_MODULE)
         if (snd_mixer_oss_notify_callback)
                 snd_mixer_oss_notify_callback(card, SND_MIXER_OSS_NOTIFY_FREE);
@@ -371,10 +359,55 @@ int snd_card_free(struct snd_card *card)
                 card->s_f_ops = s_f_ops->next;
                 kfree(s_f_ops);
         }
+        kfree(card);
+        return 0;
+}
+
+static int snd_card_free_prepare(struct snd_card *card)
+{
+        if (card == NULL)
+                return -EINVAL;
+        (void) snd_card_disconnect(card);
         mutex_lock(&snd_card_mutex);
+        snd_cards[card->number] = NULL;
         snd_cards_lock &= ~(1 << card->number);
         mutex_unlock(&snd_card_mutex);
-        kfree(card);
+#ifdef CONFIG_PM
+        wake_up(&card->power_sleep);
+#endif
+        return 0;
+}
+
+int snd_card_free_when_closed(struct snd_card *card)
+{
+        int free_now = 0;
+        int ret = snd_card_free_prepare(card);
+        if (ret)
+                return ret;
+
+        spin_lock(&card->files_lock);
+        if (card->files == NULL)
+                free_now = 1;
+        else
+                card->free_on_last_close = 1;
+        spin_unlock(&card->files_lock);
+
+        if (free_now)
+                snd_card_do_free(card);
+        return 0;
+}
+
+EXPORT_SYMBOL(snd_card_free_when_closed);
+
+int snd_card_free(struct snd_card *card)
+{
+        int ret = snd_card_free_prepare(card);
+        if (ret)
+                return ret;
+
+        /* wait, until all devices are ready for the free operation */
+        wait_event(card->shutdown_sleep, card->files == NULL);
+        snd_card_do_free(card);
         return 0;
 }
 
@@ -718,6 +751,7 @@ EXPORT_SYMBOL(snd_card_file_add);
 int snd_card_file_remove(struct snd_card *card, struct file *file)
 {
         struct snd_monitor_file *mfile, *pfile = NULL;
+        int last_close = 0;
 
         spin_lock(&card->files_lock);
         mfile = card->files;
@@ -732,9 +766,14 @@ int snd_card_file_remove(struct snd_card *card, struct file *file)
                 pfile = mfile;
                 mfile = mfile->next;
         }
-        spin_unlock(&card->files_lock);
         if (card->files == NULL)
+                last_close = 1;
+        spin_unlock(&card->files_lock);
+        if (last_close) {
                 wake_up(&card->shutdown_sleep);
+                if (card->free_on_last_close)
+                        snd_card_do_free(card);
+        }
         if (!mfile) {
                 snd_printk(KERN_ERR "ALSA card file remove problem (%p)\n", file);
                 return -ENOENT;
diff --git a/sound/core/oss/mixer_oss.c b/sound/core/oss/mixer_oss.c
index 00c95def95aa..f4c67042e3ac 100644
--- a/sound/core/oss/mixer_oss.c
+++ b/sound/core/oss/mixer_oss.c
@@ -1310,21 +1310,19 @@ static int snd_mixer_oss_notify_handler(struct snd_card *card, int cmd)
                 card->mixer_oss = mixer;
                 snd_mixer_oss_build(mixer);
                 snd_mixer_oss_proc_init(mixer);
-        } else if (cmd == SND_MIXER_OSS_NOTIFY_DISCONNECT) {
-                mixer = card->mixer_oss;
-                if (mixer == NULL || !mixer->oss_dev_alloc)
-                        return 0;
-                snd_unregister_oss_device(SNDRV_OSS_DEVICE_TYPE_MIXER, mixer->card, 0);
-                mixer->oss_dev_alloc = 0;
-        } else {                /* free */
+        } else {
                 mixer = card->mixer_oss;
                 if (mixer == NULL)
                         return 0;
+                if (mixer->oss_dev_alloc) {
 #ifdef SNDRV_OSS_INFO_DEV_MIXERS
-                snd_oss_info_unregister(SNDRV_OSS_INFO_DEV_MIXERS, mixer->card->number);
+                        snd_oss_info_unregister(SNDRV_OSS_INFO_DEV_MIXERS, mixer->card->number);
 #endif
-                if (mixer->oss_dev_alloc)
                         snd_unregister_oss_device(SNDRV_OSS_DEVICE_TYPE_MIXER, mixer->card, 0);
+                        mixer->oss_dev_alloc = 0;
+                }
+                if (cmd == SND_MIXER_OSS_NOTIFY_DISCONNECT)
+                        return 0;
                 snd_mixer_oss_proc_done(mixer);
                 return snd_mixer_oss_free1(mixer);
         }
diff --git a/sound/core/oss/pcm_oss.c b/sound/core/oss/pcm_oss.c
index a92b93e5ebd5..505b23ec4058 100644
--- a/sound/core/oss/pcm_oss.c
+++ b/sound/core/oss/pcm_oss.c
@@ -2929,25 +2929,23 @@ static int snd_pcm_oss_disconnect_minor(struct snd_pcm *pcm)
                         snd_unregister_oss_device(SNDRV_OSS_DEVICE_TYPE_PCM,
                                                   pcm->card, 1);
                 }
-        }
-        return 0;
-}
-
-static int snd_pcm_oss_unregister_minor(struct snd_pcm *pcm)
-{
-        snd_pcm_oss_disconnect_minor(pcm);
-        if (pcm->oss.reg) {
                 if (dsp_map[pcm->card->number] == (int)pcm->device) {
 #ifdef SNDRV_OSS_INFO_DEV_AUDIO
                         snd_oss_info_unregister(SNDRV_OSS_INFO_DEV_AUDIO, pcm->card->number);
 #endif
                 }
                 pcm->oss.reg = 0;
-                snd_pcm_oss_proc_done(pcm);
         }
         return 0;
 }
 
+static int snd_pcm_oss_unregister_minor(struct snd_pcm *pcm)
+{
+        snd_pcm_oss_disconnect_minor(pcm);
+        snd_pcm_oss_proc_done(pcm);
+        return 0;
+}
+
 static struct snd_pcm_notify snd_pcm_oss_notify =
 {
         .n_register =   snd_pcm_oss_register_minor,
diff --git a/sound/core/pcm.c b/sound/core/pcm.c
index b8602471f7e5..f52178abf120 100644
--- a/sound/core/pcm.c
+++ b/sound/core/pcm.c
@@ -42,7 +42,6 @@ static int snd_pcm_free(struct snd_pcm *pcm);
 static int snd_pcm_dev_free(struct snd_device *device);
 static int snd_pcm_dev_register(struct snd_device *device);
 static int snd_pcm_dev_disconnect(struct snd_device *device);
-static int snd_pcm_dev_unregister(struct snd_device *device);
 
 static struct snd_pcm *snd_pcm_search(struct snd_card *card, int device)
 {
@@ -680,7 +679,6 @@ int snd_pcm_new(struct snd_card *card, char *id, int device,
                 .dev_free = snd_pcm_dev_free,
                 .dev_register = snd_pcm_dev_register,
                 .dev_disconnect = snd_pcm_dev_disconnect,
-                .dev_unregister = snd_pcm_dev_unregister
         };
 
         snd_assert(rpcm != NULL, return -EINVAL);
@@ -724,6 +722,7 @@ static void snd_pcm_free_stream(struct snd_pcm_str * pstr)
         substream = pstr->substream;
         while (substream) {
                 substream_next = substream->next;
+                snd_pcm_timer_done(substream);
                 snd_pcm_substream_proc_done(substream);
                 kfree(substream);
                 substream = substream_next;
@@ -740,7 +739,12 @@ static void snd_pcm_free_stream(struct snd_pcm_str * pstr)
 
 static int snd_pcm_free(struct snd_pcm *pcm)
 {
+        struct snd_pcm_notify *notify;
+
         snd_assert(pcm != NULL, return -ENXIO);
+        list_for_each_entry(notify, &snd_pcm_notify_list, list) {
+                notify->n_unregister(pcm);
+        }
         if (pcm->private_free)
                 pcm->private_free(pcm);
         snd_pcm_lib_preallocate_free_for_all(pcm);
@@ -955,35 +959,22 @@ static int snd_pcm_dev_register(struct snd_device *device)
 static int snd_pcm_dev_disconnect(struct snd_device *device)
 {
         struct snd_pcm *pcm = device->device_data;
-        struct list_head *list;
+        struct snd_pcm_notify *notify;
         struct snd_pcm_substream *substream;
-        int cidx;
+        int cidx, devtype;
 
         mutex_lock(&register_mutex);
+        if (list_empty(&pcm->list))
+                goto unlock;
+
         list_del_init(&pcm->list);
         for (cidx = 0; cidx < 2; cidx++)
                 for (substream = pcm->streams[cidx].substream; substream; substream = substream->next)
                         if (substream->runtime)
                                 substream->runtime->status->state = SNDRV_PCM_STATE_DISCONNECTED;
-        list_for_each(list, &snd_pcm_notify_list) {
-                struct snd_pcm_notify *notify;
-                notify = list_entry(list, struct snd_pcm_notify, list);
+        list_for_each_entry(notify, &snd_pcm_notify_list, list) {
                 notify->n_disconnect(pcm);
         }
-        mutex_unlock(&register_mutex);
-        return 0;
-}
-
-static int snd_pcm_dev_unregister(struct snd_device *device)
-{
-        int cidx, devtype;
-        struct snd_pcm_substream *substream;
-        struct list_head *list;
-        struct snd_pcm *pcm = device->device_data;
-
-        snd_assert(pcm != NULL, return -ENXIO);
-        mutex_lock(&register_mutex);
-        list_del(&pcm->list);
         for (cidx = 0; cidx < 2; cidx++) {
                 devtype = -1;
                 switch (cidx) {
@@ -995,23 +986,20 @@ static int snd_pcm_dev_unregister(struct snd_device *device)
                         break;
                 }
                 snd_unregister_device(devtype, pcm->card, pcm->device);
-                for (substream = pcm->streams[cidx].substream; substream; substream = substream->next)
-                        snd_pcm_timer_done(substream);
-        }
-        list_for_each(list, &snd_pcm_notify_list) {
-                struct snd_pcm_notify *notify;
-                notify = list_entry(list, struct snd_pcm_notify, list);
-                notify->n_unregister(pcm);
         }
+ unlock:
         mutex_unlock(&register_mutex);
-        return snd_pcm_free(pcm);
+        return 0;
 }
 
 int snd_pcm_notify(struct snd_pcm_notify *notify, int nfree)
 {
         struct list_head *p;
 
-        snd_assert(notify != NULL && notify->n_register != NULL && notify->n_unregister != NULL, return -EINVAL);
+        snd_assert(notify != NULL &&
+                   notify->n_register != NULL &&
+                   notify->n_unregister != NULL &&
+                   notify->n_disconnect, return -EINVAL);
         mutex_lock(&register_mutex);
         if (nfree) {
                 list_del(&notify->list);
diff --git a/sound/core/rawmidi.c b/sound/core/rawmidi.c
index 51577c22f8ce..8a2bdfae63e3 100644
--- a/sound/core/rawmidi.c
+++ b/sound/core/rawmidi.c
@@ -55,7 +55,6 @@ static int snd_rawmidi_free(struct snd_rawmidi *rawmidi);
 static int snd_rawmidi_dev_free(struct snd_device *device);
 static int snd_rawmidi_dev_register(struct snd_device *device);
 static int snd_rawmidi_dev_disconnect(struct snd_device *device);
-static int snd_rawmidi_dev_unregister(struct snd_device *device);
 
 static LIST_HEAD(snd_rawmidi_devices);
 static DEFINE_MUTEX(register_mutex);
@@ -1426,7 +1425,6 @@ int snd_rawmidi_new(struct snd_card *card, char *id, int device,
                 .dev_free = snd_rawmidi_dev_free,
                 .dev_register = snd_rawmidi_dev_register,
                 .dev_disconnect = snd_rawmidi_dev_disconnect,
-                .dev_unregister = snd_rawmidi_dev_unregister
         };
 
         snd_assert(rrawmidi != NULL, return -EINVAL);
@@ -1479,6 +1477,14 @@ static void snd_rawmidi_free_substreams(struct snd_rawmidi_str *stream)
 static int snd_rawmidi_free(struct snd_rawmidi *rmidi)
 {
         snd_assert(rmidi != NULL, return -ENXIO);       
+
+        snd_info_free_entry(rmidi->proc_entry);
+        rmidi->proc_entry = NULL;
+        mutex_lock(&register_mutex);
+        if (rmidi->ops && rmidi->ops->dev_unregister)
+                rmidi->ops->dev_unregister(rmidi);
+        mutex_unlock(&register_mutex);
+
         snd_rawmidi_free_substreams(&rmidi->streams[SNDRV_RAWMIDI_STREAM_INPUT]);
         snd_rawmidi_free_substreams(&rmidi->streams[SNDRV_RAWMIDI_STREAM_OUTPUT]);
         if (rmidi->private_free)
@@ -1587,21 +1593,6 @@ static int snd_rawmidi_dev_disconnect(struct snd_device *device)
 
         mutex_lock(&register_mutex);
         list_del_init(&rmidi->list);
-        mutex_unlock(&register_mutex);
-        return 0;
-}
-
-static int snd_rawmidi_dev_unregister(struct snd_device *device)
-{
-        struct snd_rawmidi *rmidi = device->device_data;
-
-        snd_assert(rmidi != NULL, return -ENXIO);
-        mutex_lock(&register_mutex);
-        list_del(&rmidi->list);
-        if (rmidi->proc_entry) {
-                snd_info_free_entry(rmidi->proc_entry);
-                rmidi->proc_entry = NULL;
-        }
 #ifdef CONFIG_SND_OSSEMUL
         if (rmidi->ossreg) {
                 if ((int)rmidi->device == midi_map[rmidi->card->number]) {
@@ -1615,17 +1606,9 @@ static int snd_rawmidi_dev_unregister(struct snd_device *device)
                 rmidi->ossreg = 0;
         }
 #endif /* CONFIG_SND_OSSEMUL */
-        if (rmidi->ops && rmidi->ops->dev_unregister)
-                rmidi->ops->dev_unregister(rmidi);
         snd_unregister_device(SNDRV_DEVICE_TYPE_RAWMIDI, rmidi->card, rmidi->device);
         mutex_unlock(&register_mutex);
-#if defined(CONFIG_SND_SEQUENCER) || (defined(MODULE) && defined(CONFIG_SND_SEQUENCER_MODULE))
-        if (rmidi->seq_dev) {
-                snd_device_free(rmidi->card, rmidi->seq_dev);
-                rmidi->seq_dev = NULL;
-        }
-#endif
-        return snd_rawmidi_free(rmidi);
+        return 0;
 }
 
 /**
diff --git a/sound/core/rtctimer.c b/sound/core/rtctimer.c
index 84704ccb1829..412dd62b654e 100644
--- a/sound/core/rtctimer.c
+++ b/sound/core/rtctimer.c
@@ -156,7 +156,7 @@ static int __init rtctimer_init(void)
 static void __exit rtctimer_exit(void)
 {
         if (rtctimer) {
-                snd_timer_global_unregister(rtctimer);
+                snd_timer_global_free(rtctimer);
                 rtctimer = NULL;
         }
 }
diff --git a/sound/core/seq/seq_device.c b/sound/core/seq/seq_device.c
index b85954e956d4..b79d011813c0 100644
--- a/sound/core/seq/seq_device.c
+++ b/sound/core/seq/seq_device.c
@@ -90,7 +90,6 @@ static int snd_seq_device_free(struct snd_seq_device *dev);
 static int snd_seq_device_dev_free(struct snd_device *device);
 static int snd_seq_device_dev_register(struct snd_device *device);
 static int snd_seq_device_dev_disconnect(struct snd_device *device);
-static int snd_seq_device_dev_unregister(struct snd_device *device);
 
 static int init_device(struct snd_seq_device *dev, struct ops_list *ops);
 static int free_device(struct snd_seq_device *dev, struct ops_list *ops);
@@ -189,7 +188,6 @@ int snd_seq_device_new(struct snd_card *card, int device, char *id, int argsize,
                 .dev_free = snd_seq_device_dev_free,
                 .dev_register = snd_seq_device_dev_register,
                 .dev_disconnect = snd_seq_device_dev_disconnect,
-                .dev_unregister = snd_seq_device_dev_unregister
         };
 
         if (result)
@@ -309,15 +307,6 @@ static int snd_seq_device_dev_disconnect(struct snd_device *device)
 }
 
 /*
- * unregister the existing device
- */
-static int snd_seq_device_dev_unregister(struct snd_device *device)
-{
-        struct snd_seq_device *dev = device->device_data;
-        return snd_seq_device_free(dev);
-}
-
-/*
  * register device driver
  * id = driver id
  * entry = driver operators - duplicated to each instance
diff --git a/sound/core/timer.c b/sound/core/timer.c
index 52ecbe1e9abb..7e5e562fe356 100644
--- a/sound/core/timer.c
+++ b/sound/core/timer.c
@@ -88,7 +88,7 @@ static DEFINE_MUTEX(register_mutex);
 static int snd_timer_free(struct snd_timer *timer);
 static int snd_timer_dev_free(struct snd_device *device);
 static int snd_timer_dev_register(struct snd_device *device);
-static int snd_timer_dev_unregister(struct snd_device *device);
+static int snd_timer_dev_disconnect(struct snd_device *device);
 
 static void snd_timer_reschedule(struct snd_timer * timer, unsigned long ticks_left);
 
@@ -773,7 +773,7 @@ int snd_timer_new(struct snd_card *card, char *id, struct snd_timer_id *tid,
         static struct snd_device_ops ops = {
                 .dev_free = snd_timer_dev_free,
                 .dev_register = snd_timer_dev_register,
-                .dev_unregister = snd_timer_dev_unregister
+                .dev_disconnect = snd_timer_dev_disconnect,
         };
 
         snd_assert(tid != NULL, return -EINVAL);
@@ -813,6 +813,21 @@ int snd_timer_new(struct snd_card *card, char *id, struct snd_timer_id *tid,
 static int snd_timer_free(struct snd_timer *timer)
 {
         snd_assert(timer != NULL, return -ENXIO);
+
+        mutex_lock(&register_mutex);
+        if (! list_empty(&timer->open_list_head)) {
+                struct list_head *p, *n;
+                struct snd_timer_instance *ti;
+                snd_printk(KERN_WARNING "timer %p is busy?\n", timer);
+                list_for_each_safe(p, n, &timer->open_list_head) {
+                        list_del_init(p);
+                        ti = list_entry(p, struct snd_timer_instance, open_list);
+                        ti->timer = NULL;
+                }
+        }
+        list_del(&timer->device_list);
+        mutex_unlock(&register_mutex);
+
         if (timer->private_free)
                 timer->private_free(timer);
         kfree(timer);
@@ -867,30 +882,13 @@ static int snd_timer_dev_register(struct snd_device *dev)
         return 0;
 }
 
-static int snd_timer_unregister(struct snd_timer *timer)
+static int snd_timer_dev_disconnect(struct snd_device *device)
 {
-        struct list_head *p, *n;
-        struct snd_timer_instance *ti;
-
-        snd_assert(timer != NULL, return -ENXIO);
+        struct snd_timer *timer = device->device_data;
         mutex_lock(&register_mutex);
-        if (! list_empty(&timer->open_list_head)) {
-                snd_printk(KERN_WARNING "timer 0x%lx is busy?\n", (long)timer);
-                list_for_each_safe(p, n, &timer->open_list_head) {
-                        list_del_init(p);
-                        ti = list_entry(p, struct snd_timer_instance, open_list);
-                        ti->timer = NULL;
-                }
-        }
-        list_del(&timer->device_list);
+        list_del_init(&timer->device_list);
         mutex_unlock(&register_mutex);
-        return snd_timer_free(timer);
-}
-
-static int snd_timer_dev_unregister(struct snd_device *device)
-{
-        struct snd_timer *timer = device->device_data;
-        return snd_timer_unregister(timer);
+        return 0;
 }
 
 void snd_timer_notify(struct snd_timer *timer, int event, struct timespec *tstamp)
@@ -955,11 +953,6 @@ int snd_timer_global_register(struct snd_timer *timer)
         return snd_timer_dev_register(&dev);
 }
 
-int snd_timer_global_unregister(struct snd_timer *timer)
-{
-        return snd_timer_unregister(timer);
-}
-
 /*
  *  System timer
  */
@@ -1982,7 +1975,7 @@ static void __exit alsa_timer_exit(void)
         /* unregister the system timer */
         list_for_each_safe(p, n, &snd_timer_list) {
                 struct snd_timer *timer = list_entry(p, struct snd_timer, device_list);
-                snd_timer_unregister(timer);
+                snd_timer_free(timer);
         }
         snd_timer_proc_done();
 #ifdef SNDRV_OSS_INFO_DEV_TIMERS
@@ -2005,5 +1998,4 @@ EXPORT_SYMBOL(snd_timer_notify);
 EXPORT_SYMBOL(snd_timer_global_new);
 EXPORT_SYMBOL(snd_timer_global_free);
 EXPORT_SYMBOL(snd_timer_global_register);
-EXPORT_SYMBOL(snd_timer_global_unregister);
 EXPORT_SYMBOL(snd_timer_interrupt);
diff --git a/sound/pci/ac97/ac97_codec.c b/sound/pci/ac97/ac97_codec.c
index 51e83d7a839a..b35280ca2465 100644
--- a/sound/pci/ac97/ac97_codec.c
+++ b/sound/pci/ac97/ac97_codec.c
@@ -1817,13 +1817,13 @@ static int snd_ac97_dev_register(struct snd_device *device)
         return 0;
 }
 
-/* unregister ac97 codec */
-static int snd_ac97_dev_unregister(struct snd_device *device)
+/* disconnect ac97 codec */
+static int snd_ac97_dev_disconnect(struct snd_device *device)
 {
         struct snd_ac97 *ac97 = device->device_data;
         if (ac97->dev.bus)
                 device_unregister(&ac97->dev);
-        return snd_ac97_free(ac97);
+        return 0;
 }
 
 /* build_ops to do nothing */
@@ -1860,7 +1860,7 @@ int snd_ac97_mixer(struct snd_ac97_bus *bus, struct snd_ac97_template *template,
         static struct snd_device_ops ops = {
                 .dev_free =     snd_ac97_dev_free,
                 .dev_register = snd_ac97_dev_register,
-                .dev_unregister =       snd_ac97_dev_unregister,
+                .dev_disconnect =       snd_ac97_dev_disconnect,
         };
 
         snd_assert(rac97 != NULL, return -EINVAL);
diff --git a/sound/usb/usbaudio.c b/sound/usb/usbaudio.c
index 1b7f499c549d..314431385913 100644
--- a/sound/usb/usbaudio.c
+++ b/sound/usb/usbaudio.c
@@ -3499,7 +3499,7 @@ static void snd_usb_audio_disconnect(struct usb_device *dev, void *ptr)
                 }
                 usb_chip[chip->index] = NULL;
                 mutex_unlock(&register_mutex);
-                snd_card_free(card);
+                snd_card_free_when_closed(card);
         } else {
                 mutex_unlock(&register_mutex);
         }